Screw-thread gauge



R. L. ELLERY SCREW THREAD GAUGE sep1.4f, 1923. 1,467,146

Filed Feb. 26 1920 2 Sheets-Sheet 1 INYENT DE sept. 4,1923. A M6714@ R. L. ELLERY SCREW THREAD GAUGE Filed Feb. 26 1920 2 Sheets-Sheet 2 Patented Sept. 4, 1923.

narran stares meane- ROBERT 'L.- Ennnnmor TOLEDO, OHIO. Y

l SCREW'-TH:EISEN-XIII) GAUGE.

Application led'ebruary 26, 1920. Serial No. 361,389`

To @El whom t may concern.' y

Be it' known that l, ROBERT L. ELLERY, a citizen of the United States, and a resident of Toledo, in the county of Lucas and State of Ohio, have invented a certain new and. useful Screw-Thread Gauge; and lido hereby declare the following to b e a full, clear, and exact description of the invention, such as will enable others skilled in the art towhich it appertains'to make and use the saine, reference being had to the accompanying'drawings, and to the characters of reference marked thereon, which form apart of this specification. j Y

This invention relates to lead.. test gauges for the threads of screws, taps, and similar articles, and has for its object the provisionl of a simple, improved and eflicient apparatus of this character which is capable of easily and quickly finding any error in the lead` of threads in articles of the class described and is adjustable to suit threads of different lengths and diameters.

The invention is Jfully described in the following specification, and while, in its broader aspect, it is capable of embodiment in numerous forms, a preferred embodiment thereof is illustrated inthe accompanying drawings, in which,-

Figure 1 is a top `plan view of an apparat-us embodying the invention with a screw or tap in thread gauging relation thereto. Fig. 2 is a side elevation thereof with a part broken away. Fig. 3 is a front end elevation of the apparatus, and Figs. 4 and are fragment-ary sections taken .substantially on the lines e--t and 5 5 respectively in Fig. 3.

Referring to the drawings, l designates thev frame of the apparatus, which frame is illustrated, in the present instance, as of substantially triangular form and with its interior hollow. The frame at its front end,`

or that which is opposite the apex thereof, is provided in its upper portion with a horizontal slideway 2 and below said slideway with a vertical slideway 3.' In the slideway 2 ismountcd a slide block ,the adjustment of which within the slidewayl lengthwise thereof is controlled by a screw 5, which is threaded in the block and has its outer end projected through an end plate 6 of the frame for rotary but not longitudinal movements therein and provided without said plate with a control head 7. The slide block et is provided adjacent to its inner end with alforwardly projecting point 8 for pro-y jectingy into the thread groove of a screw, 7

tap or Vother article which is being tested to determine any error inits thread.r The point 8 forms the fixed thread Aengaging member ofthe gauge. i f

The movable thread engaging member of the vgauge comprises a point 9 disposed in normal predetermined vhorizontal spaced relation to `the fixed ypoint 8 at the inner side thereof and is carried at the freefend of a lever 10,- which projects rearwardly intO the .frame l andy is fulcrumed at its rear end in ythe apex portionl of the frame .forv hori zontal pivotal movements.` 'The rfree end of` this lever has an upper 4and lower bearing in adjacent to its forward or free end with an upwardly or forwardly projecting linger 11 which has lateral engagement with a gauge plunger 12 ata point in substantial vertical alignment .with the pointof engagement ofA the lever pointQ with a thread. The .gauge Y y 13 with `which the plunger 12 is connected is of the ,extremely sensitive vtype f and is adapted tol move the indicator finger- 14;V thereof upon theslightest movement of the lever A10 from normal position. As gauges of this character are oldand nothing novel is claimed therefor the gauge is not'shown in detail. v llt is preferable to provide the inner end ofthe lever 10 with a verticalbearingportion 15 having conicall bearing sockets in its opposite ends4 with which I the .respective opposed conical bearings16,'1 6 engage., These bearings are mounted for vertical adjustment in a sleeve 17 secured within the frame i 1 and are vertically adjusted therein by i in the plane of engagement of the points 8 and 9 therewith. The table is provided at the upper end of a bracket 21, which has its lower end mounted for vertical vradjustment in the trame slidway 3. The vertical adjustment of the bracket 2l to change the position of the table 2O relative to the gauge points to suit the diameter ofthe work-piece being gauged, is effected by a screw 22, which p rojects down through an opening in the top ot the frame and is threaded into a projection 2f) on the inner side of the slide portion of the bracket 2 1.

It is preferable in practice to have the lever l0 or" considerable length, as shown, as more accurate gauging ris lthereby' obtained due tothe movement of the point 9 approaching more nearly a straight line than would otherwise be vthe case "and lobtaining the advantages ot a gauge slide while avoiding objections incident to the use thereof.

It is evident that I have provided a simple and efiicient leadtest gauge for the threads oi screws, taps, or similar articles; that the iixed member of the two gauge points is adjustable to suit the length o'r size of the thread to be gauged andvto suit the master screw, and that the movable gauge point is carried yby a lever through which any relativemovemen't of the gauge point by reason ot an crroi inthe threadbeing gauged will be communicated yto the coacting 'member of an error indicating gauge 155. lt isfound in practice that with this gauge an error of twenty thousandths vof an inch or less in the thread will be accurately registered on the gauge by the ,movement of its indicator.

y' wish it understood that my 4invention is not limited to any specific construction, arrangement or form of the parts, as it is capable of numerous modications and changes without'departing from the spirit oie. the claims.

yllaving thus described my invention, what l claim as new, and desirev to secure by Letters Patent, is, i

l. In a screw thread gauge, means for supporting a work piece the screw thread of which is to be gauged, a fined point and movable point i`or` axially spaced' coaction with the threads of' a work piece when mounted on the supporting means, the fixed point being carried by said means, a lever carrying the movable point for movements axially ot a work piece disposed ,in gauging position onthe supporting means, and means connected to the lever at substantially the same distance from its tulcrum nas the movable ,point and operable'by movements of the lever to indicate any relative movement of the points.

l2. In a screw thread gauge, a support Jior a work piece the screw thread of which is "tob'e gauged, a pair of work thread gauging points one of which points is fixed and the other movable and spaced axially ot a work piece to .be gauged, means carrying the fixed point and manually adjustable to suit the length or size of a thread to be gaugcd and of a master screw, a member mounted Jfor free horizontal swinging movements and carrying the movable point a considerable distance from the axis o't VJthe swinging member, and means connected to the member at substantially the same distance from the axis thereof as the vmovable point and operable by movements of the member to indicate any relative movements of the points when engaged with a work piece.

3. .In a screw ,thread gauge, a frame, a work support carried'on'the frame for vertical adjustment, a member carried for horizontal adjustment by the iframe over and adjacent to the support, separate means operable to respectively adjust Vthe support and member, a lined work thread gauge pointy carried by the member, an arm of considerable length mounted for tree horizontal swinging movements and having a movable work thread gauge carried by the arm in adjacent horizontal lspaced relation to the i'ined point, the points being spaced axially of a work piece disposed in gauging position on the support, and means acted on by the arm adjacent to the movable point in laterally spaced relation thereto to indicate any relative movement of the points duringA a gauging operation.

t. In a gauge apparatus of the class described, a frame having a horizontal slideway therein, a slide block in said way, means manually operable to vadjust the slide block, a fixed gauge point carried by said block for adjustment therewith, a lever fulcrumed in the frame at a distance from said fixed point rearwardly thereof and mounted for horizontal swinging movements transverse to said point, a movable gauge point carried by said lever at a side of the fixed point, means acted on by the lever to indicate any relative movement of the points during a gauging operation, and an adjustable means for supporting a work-piece in gauging relation to said points.

In ltestimony whereof, 1 have hereunto signed my name to this specification.

ROBERT L. ELLERY. 

